Propagating plants (that is, growing new plants from old ones) by cutting off stems is an easy procedure. Typically, however, it's done by cutting fresh stems from a plant and trying to root them the same day. Still, plants can sometimes be rooted if they've been cut for a longer period of time. For example, it's possible to root cut roses you receive in a gift bouquet. It's important to note, however, that if the plant you try to root is a hybrid, you may not end up with a new plant that looks exactly like the mother plant.
Remove a cut flower from its vase as soon as possible. Cut flowers that have been kept cool and moist have the highest rooting success rate.
Cut the bottom of the flower stem at a 45 degree angle just above a node (the bump where a leaf will eventually grow), using clean hand pruning shears or sharp, clean scissors. Washing the pruners or scissors in hot, soapy water or wiping them down with rubbing alcohol helps keep the cut stem healthy.
Cut the flower and all of the stem above the first set of leaves.
Spritz a clear plastic bag with water.
Place the stem inside the plastic bag and place in the refrigerator. This will keep it cool and moist as you prepare a pot.
Wash a pot in hot, soapy water and rinse well.
Fill the pot with a mixture of one part peat and one part perlite, or one part coarse river sand and one part peat. Water well and allow to drain.
Remove the cutting from the plastic bag and dip it in rooting hormone. Gently tap the stem to remove any excess hormone.
Place the bottom of the cutting into the pot, at least two inches deep.
Place the plastic bag over the stem. This will create a mini-greenhouse that will keep the cutting warm and moist. Place in an indoor location that receives indirect sunlight.
Check the cutting every day; if the soil starts drying, lift the bag and spray the soil with water, then replace the bag.
Tug gently on the cutting, after a few weeks, to see if it has rooted. Once rooted, gradually remove the plastic bag, lifting it an inch or so every day until the cutting is acclimated to the air in your home.
Place the rooted cutting outdoors in indirect light in the late spring or summer. Gradually move the plant into the sunlight it requires.